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Our programs produce accurate geologic maps and 3-D geologic frameworks that provide critical data for sustaining and improving the quality of life and economic vitality of the Nation. 

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Bedrock topography of north-central Iowa Bedrock topography of north-central Iowa

The bedrock in Iowa (Hershey, 1969) is generally overlain by deposits of glacial drift and alluvium, which range in thickness from less than 1 ft to more than 400 ft, and from less than 1 ft to about 60 ft respectively. The configuration of the bedrock surface is the result of a complex system of ancient drainage courses which were developed during a long period of preglacial erosion and...
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